Unit, device and system for preparing beverage consumptions

ABSTRACT

The beverage preparation unit comprises a mixing chamber having a beverage outlet, a liquid flow path for supplying a liquid to the mixing chamber, and an air flow path for supplying air to the liquid flow path. The mixing chamber is arranged for receiving a beverage related ingredient, such as concentrate, preferably from an exchangeable supply pack. The liquid flow path is arranged for generating a hollow jet of liquid having an outer liquid portion extending in a flow direction of the jet and an inner air portion extending in a flow direction of the jet wherein the outer liquid portion surrounds the inner air portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT/EP2015/079886, filed Dec. 15,2015, which claims the benefit of and priority to NetherlandsApplication No. NL2013987, filed Dec. 15, 2014, the entire contents ofall of which are incorporated herein by reference.

BACKGROUND

The invention relates to a system for preparing beverage consumptionsfrom a beverage related ingredient for example concentrate. Examples ofbeverage related concentrates are coffee concentrate, cocoa concentrate,tea concentrate and milk concentrate. Such systems are provided with amixing chamber, liquid supply means for supplying a liquid such as waterto the mixing chamber, and means for supplying a beverage relatedingredient, such as concentrate to the mixing chamber. Additionally thesystem may include means for supplying air to the mixing chamber inorder to produce beverage consumptions with a foam layer.

Such systems are known in the art. In systems where a beverage relatedingredient is mixed with a liquid in a mixing chamber the mixing chamberand liquid and/or ingredient supply means may become soiled withresidues from the mixture. The mixture residue may eventually cause thesystem to clog, and/or may even result in undesired bacterial growth.Additionally consumers are becoming ever more critical with regard tothe appearance of the produced beverage consumptions. This is especiallytrue for systems where a beverage related ingredient, such asconcentrate, is mixed with a liquid, such as water, in a mixing chamber.

SUMMARY

Therefore it is an object of the invention to provide an improved systemfor preparing beverage consumptions. Additionally, and/or alternatively,it is an object of the invention to provide a system with improvedhygiene. Additionally, and/or alternatively, it is an object of theinvention to provide a system the produces beverage consumptions with animproved foam layer.

Thereto according to the invention a system for preparing beverageconsumptions such as coffee, tea, cappuccino, lungo, expresso, etc. isprovided. The system comprises a beverage preparation device, and atleast one exchangeable supply pack arranged for holding a beveragerelated ingredient. The beverage related ingredient may be aconcentrate. Examples of beverage related concentrates are coffeeconcentrate, cocoa concentrate, tea concentrate and milk concentrate.The beverage preparation device comprises a mixing chamber having abeverage outlet, liquid supply means including a liquid flow path forsupplying a liquid, for example water under pressure, to the mixingchamber, air supply means for supplying air to the liquid flow path, anda drive shaft. The at least one exchangeable supply pack includes acontainer for holding a beverage related ingredient, and a doser havingan outlet. The doser is arranged for supplying the beverage relatedingredient from the container to the outlet of the doser in a dosedmanner. The at least one exchangeable supply pack and the beveragepreparation device are mechanically connectable. When connected, theoutlet of the doser is brought in fluid communication with the mixingchamber and the drive shaft of the beverage preparation device isarranged for transmitting torque from the beverage preparation device tothe doser such that when the drive shaft is activated beverage relatedingredient is supplied from the outlet of the doser into the mixingchamber. The mixing chamber is provided with a supply opening forreceiving concentrate from the doser of the at least one exchangeablesupply pack. For example the supply opening may be located towards a topof the mixing chamber such that the beverage related ingredient may flowfrom the outlet of the doser into the mixing chamber substantially underthe influence of gravity. When the supply opening is located towards thetop of the mixing chamber, a functional height can be defined as thebottom of the mixing chamber to the level of the mixing chamber wherethe doser outlet is located. The functional height is in the range of 15mm-100 mm, preferably 20 mm-80 mm, and more preferably 20 mm-40 mm. Itwill be appreciated that the functional height of the mixing chamber isthe height of the mixing chamber in which the beverage may be mixed. Thefunctional height is delimited by the doser and the outlet of the mixingchamber.

It will be appreciated that a drive shaft is one example of a doserinterface for activating the doser for supplying beverage relatedingredient from the outlet of the doser into the mixing chamber.

Optionally, the beverage preparation device is arranged to rotate thedrive shaft at X RPM wherein X lays in the range of 20-5000 andpreferably in the range of 50-2200, wherein the doser is arranged suchthat if the doser is driven with X RPM, the doser doses the ingredientwith C*X/60 ml/sec wherein C lays in the range of 0.05-1 and preferablyin the range of 0.1-0.3. C is the volume of beverage related ingredientper revolution of the drive shaft. It has been found that thisrelationship between the revolutions per minute of the drive shaft andthe amount of ingredient dosed by the doser produces beverageconsumptions with the desired strength and flavor.

Optionally, the system is arranged such that, in use for the preparationof a beverage the torque which is applied by the drive shaft to thedoser lays in the range of 0.1-0.8 Nm, and preferably in the range of0.15-0.45 Nm. It has been found that transmitting torque from the driveshaft to the doser in the above ranges results in the desired dosing.

Optionally, the beverage preparation device is arranged to dose Z ml ofliquid for the one beverage into the mixing chamber wherein Z lays inthe range of 2-10000, and preferably in the range of 10-300, and whereinthe system is arranged to dose Y ml beverage related ingredient into themixing chamber for the preparation of one beverage wherein Y lays in therange of 0.1-5000, and preferably in the range of 1-100. It has beenfound that when the device doses the above range of liquid to the mixingchamber, it is desirable that the system doses the above range ofbeverage related ingredient to the mixing chamber in order toconsistently produce beverage consumptions with the desired strength andflavor.

Optionally, the beverage preparation device is arranged to dose Z ml ofliquid into the mixing chamber for the one beverage wherein Z lays inthe range of 2-10000, and preferably in the range of 10-300, and whereinthe system is arranged to dose D*Z ml beverage related ingredient intothe mixing chamber for the preparation of one beverage wherein D lays inthe range of 0.02-0.5, and preferably in the range of 0.04-0.3. D is theratio of the volume of beverage related ingredient to volume of liquidfor preparing one beverage. It has been found that this relationshipbetween the amount of liquid dosed to the mixing chamber, and thebeverage related ingredient dosed by the system consistently producesbeverages with the desired strength and flavor.

Optionally, the beverage preparation device is arranged such that forpreparation of the one beverage the liquid is dosed to the mixingchamber on average with Q ml/sec wherein Q lays in the range of 5-30 andpreferably in the range of 8-12, and wherein the system is arranged suchthat for the preparation of the one beverage the ingredient is dosedinto the mixing chamber on average with R ml/sec wherein R lays in therange of 0.1-15, and preferably in the range of 0.32-3.6. R is the flowof beverage related ingredient to the mixing chamber. It has been foundthat with device flows rates in the ranges above, it is desirable thatthe system doses the beverage related ingredient in the above ranges inorder to produce a beverage with the desired strength and flavorconsistently.

Optionally, the beverage preparation device is arranged such that forpreparation of the one beverage the liquid is dosed to the mixingchamber on average with Q ml/sec wherein Q lays in the range of 5-30 andpreferably in the range of 8-12, and wherein the system is arranged suchthat for the preparation of the one beverage the ingredient is dosedinto the mixing chamber on average with F*Q ml/sec wherein F lays in therange of 0.02-0.5 and preferably in the range of 0.04-0.3. F is theratio of beverage related ingredient flow to liquid flow for preparingone beverage. It has been found that this relationship between theliquid dose rate and the beverage related ingredient dose rate producesa beverage with the desired strength and flavor.

Optionally, the beverage preparation device is arranged such that forthe preparation of the one beverage the liquid is dosed in the form of ajet into the mixing chamber wherein the jet on average has a speed of Vm/sec wherein V lays in the range of 4-30, and preferably in the rangeof 6-20. It has been found that jets having on average a speed in theabove ranges promotes mixing of the liquid and the beverage relatedingredient and may improve foam production.

Optionally, the beverage preparation device is arranged such that if forthe preparation of the one beverage the liquid is dosed in the form of ajet into the mixing chamber with Q ml/sec, wherein preferably Q lays inthe range of 5-30 and preferably in the range of 8-12, the speed of thejet is Q/E wherein E is the cross-surface area of the liquid of the jetin mm² wherein E lays within the range of 0.17-7.5, and preferably inthe range of 0.4-2. It has been found that the above relationshipbetween the flow rate of liquid to the mixing chamber and the speed ofthe jet promotes mixing while producing a beverage consumption in anacceptable amount of time.

Optionally, the beverage preparation device is arranged such that forthe preparation of the one beverage the liquid is dosed to the mixingchamber during G seconds wherein G lays in the range of 0.5-10000, andpreferably in the range of 1-30. It has been found that the above rangesproduce beverage consumptions in an acceptable amount of time.

Optionally, the liquid supply means is arranged for supplying liquid tothe mixing chamber at a flow rate of 5-30 ml/sec, and preferably 8-12ml/sec. It has been found that such flow rates produce beverageconsumptions in an acceptable amount of time.

Optionally, the liquid supply means is arranged for generating a jet ofliquid having a stable speed of 4-30 m/sec and preferably 6-20 m/sec. Itwill be appreciated that stable speed is the speed of the jet when theliquid supply means have reached a stable state. The liquid supply meansmay, for example, have a ramp up state where a jet of liquid is producedbefore reaching a stable state. There may also be a ramp down state whenthe liquid supply means is disable. It has been found that jets havingstable speeds in abovementioned ranges promote mixing of the beveragerelated ingredient as well as foam production. In addition, jets havingstable speeds in the abovementioned ranges may improve hygiene.

Optionally, the beverage preparation device and the doser of the atleast one exchangeable supply pack are arranged for supplying beveragerelated ingredient, for example concentrate, to the mixing chamber at arate of 0-14 ml/sec, and preferably 0-7 ml/sec. It has been found thatsuch flow rates produce beverage consumptions in an acceptable amount oftime.

Optionally, during a beverage cycle for preparing a beverageconsumption, the beverage preparation device is arranged for activatingthe drive shaft for 0.5-1000 seconds, preferably 0.5-30 seconds.

Optionally, during a beverage cycle for preparing a beverageconsumption, the doser is arranged for dosing 0.1-5000 ml of beveragerelated ingredient when the drive shaft is activated for 0.05-1000seconds. Optionally, during preparation of a beverage consumption, thedoser is arranged for dosing 1-100 ml of beverage related ingredientwhen the drive shaft is activated for 0.5-30 seconds. It has been foundthat exchangeable supply packs having dosers that supply the aboveranges of beverage related ingredient when activated by the beveragepreparation device for the above ranges provide beverage consumptionswith the desired strength and flavor within a desired amount of time.The desired amount of time, may be driven by the configuration of theliquid supply means or even by what the consumer finds to be anacceptable amount of time to wait for the beverage consumption.

Optionally, the doser is arranged for dosing 0.05-1.0 ml of beveragerelated ingredient per drive shaft revolution, and preferably 0.1-0.3 mlof beverage related ingredient per drive shaft revolution. Thisrelationship has been found to meet system and consumer demands.

Optionally, the beverage preparation device is arranged for operatingthe drive shaft, during activation, at substantially 20-5000 revolutionsper minute, and preferably 50-2200 revolutions per minute (RPM). It willbe appreciated that the operation of the drive shaft may have a ramp upphase, where the revolutions per minute are lower than a target numberof revolutions per minute. For example, if driven by a stepper motor,the motor may start at a first RPM. During a ramp up phase, the RPM ofthe motor may be incrementally increased, for example every 50 msec,until the target RPM is reached.

Optionally, during a beverage cycle for preparing a beverageconsumption, the doser is arranged for dosing 1-100 ml of beveragerelated ingredient when the drive shaft is activated for 0.5-30 secondsat substantially 50-2200 revolutions per minute. Optionally, duringpreparation of a beverage consumption, the doser is arranged for dosing0.1-5000 ml of beverage related ingredient when the drive shaft isactivated for 0.05-1000 seconds at substantially 20-5000 revolutions perminute. The above ranges have been found to produce beverageconsumptions having desired characteristics such as strength and flavorin an acceptable amount of time.

Optionally, the beverage preparation device is arranged for operatingthe drive shaft, during activation, in order to transmit torque to thedoser greater than 0.05 Nm, preferably greater than 0.1 Nm, and mostpreferably greater than 0.2 Nm. It has been found that it is desirableif a predetermined amount of torque is required to be transmitted fromthe drive shaft to the doser in order to activate the doser. This mayimprove accuracy.

Optionally, during a beverage cycle for preparing a beverageconsumption, the doser is arranged for dosing 1-100 ml of beveragerelated ingredient when the drive shaft is activated for 0.5-30 secondsat substantially 50-2200 revolutions per minute and wherein the driveshaft transmits more than 0.2 Nm of torque to the doser. It has beenfound that in these conditions a desired beverage consumption isproduced in a desired amount of time.

Optionally, during a beverage cycle for preparing a beverageconsumption, the beverage preparation device is arranged for activatingthe liquid supply means for a period of 0.5-1000 seconds, and preferably1-30 seconds. Optionally, during a beverage cycle for preparing abeverage consumption, the beverage preparation device is arranged foractivating the liquid supply means for a period of 0.5-1000 seconds, andpreferably 1-30 seconds, and wherein during the period of activation ofthe liquid supply means, the beverage preparation device is furtherarranged for activating the drive shaft such that 0.1-5000 ml, andpreferably 1-100 ml of beverage related ingredient is supplied from theoutlet of the doser to the mixing chamber. This results in 5-10000 ml ofdrink volume and preferably 15-300 ml of drink volume. In this way thesystem can also produce a range of beverage volumes, while maintainingbeverage quality.

Optionally, the mixing chamber has a volume of 1-20 ml, preferably 2-8ml, and most preferably 4-5 ml. It has been found that for the operatingranges of the system, such as liquid supply means, drive shaft anddoser, this volume range of the mixing chamber produces a beverageconsumption having the desired characteristics. These volume ranges mayalso promote foam formation.

Optionally, during a beverage cycle for preparing a beverageconsumption, the beverage preparation device is arranged for activatingthe liquid supply means for a first period of time and for activatingthe drive shaft for a second period of time, wherein the first period oftime and the second period of time overlap. Optionally, during the firstperiod, the liquid supply means is arranged for supplying 2-10000 ml ofliquid, and preferably 10-290 ml of liquid, and wherein the doser isarranged for supplying 0.1-5000 ml of beverage related ingredient, andpreferably 1-100 ml of beverage related ingredient during the activationof the drive shaft for the second period of time. It has been found thatthese supply ranges produce a desired beverage consumption in a desiredamount of time.

Optionally, the first period begins 0-1 seconds before the secondperiod. Activating the liquid supply means prior to activating the driveshaft in order to drive the doser and supply beverage related ingredientto the mixing chamber may promote better mixing. Optionally, during abeverage cycle, the beverage preparation device is arranged foractivating the liquid supply means prior to activating the drive shaftfor driving the doser of the at least one exchangeable supply pack, andwherein preferably the drive shaft is activated 0-1 seconds afteractivation of the liquid supply means.

Optionally, wherein the second period ends 0-5 seconds, and preferably0-3 seconds before the first period ends. In this way, the liquid supplymeans remains activate, at the end of a beverage cycle, after the devicestops driving the doser. This has been found to promote hygiene, as theprolonged activation of the liquid supply means rinses the mixingchamber.

Optionally, at the end of a beverage cycle, the beverage preparationdevice is arranged for activating the liquid supply means after thebeverage preparation device has stopped activation of the drive shaft.Conceivably, the liquid supply means may be continued to be activated,or alternatively be reactivated, at the end of the beverage cycle. Againthis has been found to promote hygiene and reduce mixture residue buildup.

In this case it is desirable that the beverage preparation device isarranged for activating the liquid supply means after the beveragepreparation device has stopped activation of the drive shaft for aperiod of 0-5 seconds, and more preferably 0-3 seconds.

Optionally, at the end of the beverage cycle, the beverage preparationdevice is arranged for activating the liquid supply means after thebeverage preparation device has stopped activation of the drive shaftsuch that 5-30 ml and preferably 8-15 ml of water are supplied to themixing chamber. This amount of liquid has been found to sufficientlyrinse the mixing chamber especially, when the mixing chamber has avolume of 1-20 ml, preferably 2-8 ml, and most preferably 4-5 ml. Inaddition to rinsing the mixing chamber, this amount of liquid causes themixing chamber to fill and rinses the fluid connection between theoutlet of the doser and the mixing chamber. Preferably, the mixingchamber is tapered such that diameter widens in an upward verticaldirection, and wherein liquid supplied by the liquid supply means afterthe beverage preparation device has stopped activation of the driveshaft is directed upwardly by the tapered mixing chamber such that theliquid level rises in the mixing chamber and cleans the outlet of thedoser, and in particular cleans an outlet valve of the doser.Optionally, the beverage preparation device is arranged for activatingthe liquid supply means such that 5-30 ml and preferably 8-15 ml ofwater are supplied to the mixing chamber, and during activation of theliquid supply means the beverage preparation machine does not activatethe drive shaft. As mentioned above, this amount of liquid has beenfound to sufficiently rinse the mixing chamber and the fluid connectionbetween the outlet of the doser and the mixing chamber, including anoutlet of the doser. In this way a cleaning cycle may be performedindependent of a beverage cycle. For example, a cleaning cycle may beperformed at any preprogrammed time.

Optionally, the doser comprises a pump assembly including a pump channelbetween an inlet and an outlet for receiving the beverage relatedingredient from the container of said pack and for pumping theingredient to the outlet.

Optionally, the pump assembly further comprises a pump chamber and atleast two mutually engaging gears forming a gear pump arranged in saidpump chamber, wherein at least one of said gears forms a driving gear,the driving gear comprising a shaft opening for receiving the driveshaft of the beverage preparation device for operating the gear pump.

Optionally, the shaft opening coincides with an axle reception openingof a support wall of the pump chamber, and wherein a flexible seal isarranged at least between the driving gear and the support wall, whereinthe seal comprises a through opening coinciding with the shaft openingand the axle reception opening for receiving the driving axle. Thisdoser has been found to work well in such a system.

Optionally, the liquid supply means is arranged for supplying the liquidinto the mixing chamber in the form of a jet.

Optionally, the liquid flow path includes a first nozzle and the liquidflow path is arranged for generating a hollow jet of liquid having anouter liquid portion extending in a flow direction of the jet and aninner air portion extending in a flow direction of the jet wherein theouter liquid portion surrounds the inner air portion. In this way thehollow jet has the form of a straw wherein the inner side of the strawrepresents the inner air portion of the jet and the straw itselfrepresents the outer liquid portion of the jet. Thus the hollow jet infact is a combination of an jet of air and a hollow jet of liquid whichsurrounds the jet of air. The flow direction of the jet of air and theflow direction of the hollow jet of liquid is the same. It has beenfound that a hollow jet is a effective manner to supply both liquid andair to the mixing chamber. Optionally, the first nozzle has an taperedgeometry wherein over the flow direction of the nozzle, the opening ofthe nozzle decreases exponentially.

In this way a beverage preparation unit for preparing beverageconsumptions using a beverage related ingredient is provided. Thebeverage preparation unit comprises a mixing chamber having a beverageoutlet, a liquid flow path for supplying a liquid to the mixing chamber;and an air flow path for supplying air to the liquid flow path themixing chamber is arranged for receiving a beverage related ingredient,such as concentrate, preferably from an exchangeable supply pack. Theliquid flow path is arranged for generating a hollow jet of liquidhaving an outer liquid portion extending in a flow direction of the jetand an inner air portion extending in a flow direction of the jetwherein the outer liquid portion surrounds the inner air portion.Optionally, the liquid flow path and the air flow path are arranged forforming the hollow jet. The hollow jet is formed through the interactionand/or cooperation of the liquid flow path and the air flow path.

In one possible embodiment the flow of liquid in the liquid flow pathextends in an axial direction, wherein the system is further providedwith air injection means for generating a flow of air which extends inthe axial direction and for injecting the flow of air substantiallycoaxially in the flow of liquid in the flow path (meaning that an axialaxe of the flow of liquid in the flow path coincides with an axial axeof the flow of air) wherein the flow direction of the flow of liquid inthe flow path is the same as the flow direction of the flow of air so asto obtain the hollow jet.

Thus it may hold that the jet which is (finally) generated comprises anaxial direction, wherein the system is further provided with airinjection means for generating a flow of air which extends in the axialdirection and for injecting the flow of air substantially coaxially inthe jet wherein the flow direction of the jet is the same as the flowdirection of the flow of air so as to obtain the hollow jet.

Thus it may hold that the jet which is (finally) generated extends in anaxial direction of the jet, wherein the system is further provided withair injection means for generating a flow of air and injecting the flowof air substantially coaxially in the jet wherein the flow direction ofthe jet is the same as the flow direction of the flow of air so as toobtain the hollow jet.

Optionally, the injection means comprise a needle having an open endwherein an axial direction of the needle and an the axial direction ofthe jet at least substantially coincide. Preferably the length of aportion of the needle extending along the axial direction in the liquidflow path is in the range of 1 mm-10 mm, preferably in the range of 2.5mm-5 mm, and more preferably in the range of 3 mm-4.5 mm.

Optionally, the open end of the needle is located near the first nozzlewherein the needle extends from the open end in a direction opposite tothe flow direction of the jet.

Optionally, the open end of the needle is located in the nozzle, streamupwards of the nozzle or stream downwards of the nozzle. Preferably theopen end of the needle is spaced between 0 mm-5 mm, preferably 0 mm-2mm, most preferably 0 mm-0.5 mm from the opening of the nozzle.Optionally, the inner diameter of the needle is between 0.1 mm and 0.5mm.

Optionally, the first nozzle is arranged for generating a jet of liquidin an axial direction, and wherein the liquid flow path includes airinjection means for injecting a stream of air towards a center of thejet of liquid in a direction substantially coaxial with the axialdirection of the jet of liquid such that a hollow jet is formed.

Optionally, the air injection means include a pipe extending into thefirst nozzle, wherein the pipe is substantially coaxial with the firstnozzle, and wherein the air injection means is arranged for injectingair into the jet of liquid generated by the first nozzle through thepipe.

Optionally, the air injection means is arranged to be in fluidcommunication with an air pump.

Optionally, the liquid flow path includes a selection valve comprising avalve body, a liquid inlet, an air inlet, and at least a first outlet.It will be appreciated that by includes it is intended that the liquidflow path runs through the valve. The liquid inlet is in fluidcommunication with the liquid supply means. The air inlet is in fluidcommunication with the air supply means. The at least first outlet is influid communication with the mixing chamber. The selection valve furthercomprises a selector member including a portion of the air injectionmeans, for example the needle. The selector member is movably mountedwith respect to the valve body for movement from a first position inwhich the liquid inlet is in fluid communication with the at least firstoutlet, and wherein the air inlet is in fluid communication with the atleast first outlet via the needle of the selector member. In this way ahollow jet may be generated with the selection valve. Preferably theselector member is slidably mounted such that portions of valve elementsmay slide in and out of the liquid flow path. Preferably, the firstnozzle is located downstream of the selector member. More preferably,the first nozzle is included in the valve. Preferably the selector ismovable is a direction perpendicular to the flow of the liquid into themixing chamber. Preferably, the selector is movable is a direction thatis perpendicular to that of an axial axe of the flow of liquid in theflow path that coincides with an axial axe of the flow of air. In thisway movement of the selector is perpendicular to the flow direction ofthe flow of liquid in the flow path which is the same as the flowdirection of the flow of air for obtaining the hollow jet. Preferablymovement of the selector is a rotational movement in the planesubstantially perpendicular to the flow of liquid to the mixing chamber.

Optionally, the selector member comprises a ceramic element, preferablyshaped as a disc, and provided with an opening, wherein the needleextends axially within the opening. In this way liquid from the liquidinlet and liquid supply means may flow around the needle with a liquidflow path extending in an axial direction. The needle provides airinjection means for generating a flow of air which extends in the axialdirection and for injecting the flow of air substantially coaxially inthe flow of liquid in the flow path. This forms a hollow jet, whichsubsequently flows through the first nozzle and exits the valve via theat least first outlet and into the mixing chamber.

Optionally, the selector member is movable to a second position in whichthe liquid inlet is in fluid communication with the at least firstoutlet. In the second position, fluid communication from the air inletto the at least first outlet is shut off. It will be appreciated that inthe second position a fluid connection between the air inlet and the atleast first outlet is not formed or is no longer formed, i.e. it isblocked, for example by the selector member. In this way, the selectionvalve incorporates an air valve for selectively supplying air to theneedle for forming a hollow jet.

Optionally, the selector member is movable to a third position in whichfluid communication from the liquid inlet to the at least first outletis shut off. In this position fluid communication from the air inlet tothe at least first outlet is shut off, is not formed, no longer formed,or it is blocked, for example by the selector member. In this way thepressure in from the liquid supply means of the device may be maintainedif for example a plurality of, for example two, beverage preparationunits were provided in the beverage preparation device. For, example oneunit may be provided for a coffee related beverage ingredient andanother unit may be provided for a milk related beverage ingredient.When a coffee beverage without milk is being produced the milk beveragepreparation unit may be placed in the third position such that pressureof the liquid supply means may be maintained.

Optionally, the valve has a second outlet in fluid communication with areservoir of the system. The selector member is movable to a fourthposition wherein the liquid inlet is in fluid communication with thesecond outlet. In this position preferably fluid communication from theliquid inlet to the at least one outlet and fluid communication from theair inlet to the at least first outlet is shut off. The second outlet isa bypass outlet. This position is useful for preventing boiler pressurebuildup and to allow removal of air from the boiler at the beginning ofthe drink production process.

Optionally, the valve further includes a satellite element including thefirst nozzle. The satellite member is associated with the selectormember, and the satellite element has a predefined limited amount offree relative movement with respect to the selector member. Thereforethe satellite element may be positioned independently of the selectormember. However preferably the satellite member is movable is the samedirection as the selector member. In the first position the liquid inletand air inlet are in fluid communication through a fluid flow pathincluding the first nozzle of the satellite member. It will beappreciated that the fluid flow path comprises the first nozzle and thatit is not limited to only the first nozzle. For example the fluid flowpath may include the air inlet and needle as well as the liquid inletand the opening around the needle for allowing water to flow axiallyalong the needle to the point where air is injected.

Optionally, the satellite element is further provided with an additionalnozzle of a different geometry than that of the first nozzle. In thesecond position, the liquid inlet is in fluid communication with the atleast first outlet through a fluid flow path including the additionalnozzle. By allowing different nozzles of the satellite element to formthe fluid flow path different beverages may be brewed.

Optionally, the selector member is provided with a second opening remotefrom the first opening. Preferably, in the second position, the liquidinlet is in fluid communication with the at least first outlet through afluid flow path including the second opening.

In one example the additional nozzle is the substantially the samediameter as an opening forming the at least first outlet. With the fluidflow path including the second opening in the selector member, alsochosen to be substantially the same diameter as the opening forming theat least first outlet, a fluid flow path may be formed for generating asolid jet having a relatively larger diameter. Such a jet is useful forforming foamless beverages.

When the valve is in the third position, the at least first outlet maybe vented. This advantageously allows the mixing chamber to drain. If asatellite element is provided the vent may be provided by a channel inthe satellite element.

In another possible embodiment the liquid flow path includes the firstnozzle which is arranged for generating a hollow jet of liquid having anouter liquid portion extending in a flow direction of the jet and aninner air portion extending in a flow direction of the jet wherein theouter liquid portion surrounds the inner air portion.

Optionally, the first nozzle terminates at a side wall of the mixingchamber, and wherein the outer liquid portion of the jet contacts asubstantial portion of an inner surface of the first nozzle in an areaadjacent to the mixing chamber. In this way the outer liquid portion ofthe jet sealingly contacts most of an inner surface of the first nozzlein the area adjacent to the mixing chamber. This prevents beveragerelated ingredient from flowing out of the mixing chamber and into theliquid flow path. In this way mixture residue buildup may be reduced.

Optionally, the first nozzle tapers towards the mixing chamber, andwherein the liquid flow path comprises a second nozzle located upstreamfrom the first nozzle and arranged for generating a substantially solidjet of liquid, wherein the nozzles are positioned relative to each othersuch that the substantially solid jet of liquid, is at least surroundedpartially by air, and impacts an inner surface of the first nozzle in animpact zone causing the jet to swirl around the inner surface of thefirst nozzle thus forming a hollow jet of liquid. Preferably, the firstand second nozzle are positioned relative to each other such that thesubstantially solid jet is off-centered with respect to a center of thefirst nozzle.

In this way a hollow jet of liquid is formed. Through the impact againstthe first nozzle, which may be for example cone shaped, the liquid isdirected outwardly and the air partially surrounding the substantiallysolid jet of liquid is directed inwardly, thereby forming a hollow jetof liquid.

Optionally or alternatively, the liquid flow path includes a firstnozzle arranged for generating a substantially solid jet of liquid. Thefirst nozzle terminates at a side wall of the mixing chamber, and theliquid of the substantially solid jet contacts a substantial portion ofan inner surface of the first nozzle in an area adjacent to the mixingchamber. In this way, a drink having a reduced foam layer may beproduced, as the solid jet does not supply air to the mixing chamber.However, it is conceivable that air is supplied by other means to thechamber, for example by a separate air inlet, and that a beverage havinga foam layer may be produced by the solid jet.

Optionally, the first nozzle tapers towards the mixing chamber, and theliquid flow path comprises a second nozzle located upstream from thefirst nozzle and arranged for generating a substantially solid jet ofliquid. The first and second nozzle are positioned relative to eachother such that the substantially solid jet of liquid is centered withrespect to a center of the first nozzle. As the substantially solid jetis centered with respect to the center of the first nozzle, the impactdoes not cause the jet to swirl around the inner surface of the firstnozzle and thus the jet remains substantially solid.

Optionally the first and second nozzle are relatively movable between atleast a first and a second position. In the first position the first andsecond nozzle are positioned relative to each other such that thesubstantially solid jet is off-centered with respect to a center of thefirst nozzle. In the second position the first ands second nozzle arepositioned relative to each other such that the substantially solid jetof liquid is centered with respect to a center of the first nozzle. Inthe first position, the liquid supply means is arranged for supplying ahollow jet of liquid to the mixing chamber. This is a effective mannerto supply both liquid and air to the mixing chamber, and to produce abeverage having a foam layer. In the second position, the liquid supplymeans is arranged for supplying a substantially solid jet to the mixingchamber. This may be useful in producing beverages having a reduced foamlayer, or where a foam layer is not desirable. In both cases, the liquidof the jet sealingly contacts most of the inner surface of the firstnozzle in the area adjacent to the mixing chamber, which preventsbeverage related ingredient from flowing out of the mixing chamber andinto the liquid flow path.

Preferably, the first nozzle is stationary and the second nozzle ismovable relative to the first nozzle.

Preferably, the first nozzle is substantially cone shaped.

Optionally, the liquid flow path further comprises an intermediateportion separating the first nozzle from the second nozzle, and whereinthe liquid flow path is arranged such that air flow around thesubstantially solid jet is possible. It will be appreciated that the airflow about the substantially solid jet of liquid may be made possible bythe size, for example cross section, and/or position of the intermediateportion.

Optionally, the liquid flow path further comprises an intermediateportion separating the first nozzle from the second nozzle, and whereinthe liquid flow path is arranged such that the substantially solid jettravels, in steady state, from the second nozzle to the impact zone ofthe first nozzle without contacting an inner surface of the intermediateportion.

Optionally, the air supply means comprise an air supply duct in fluidcommunication with the liquid flow path and located upstream from thefirst nozzle, and preferably the air supply duct is connected to theintermediate portion of the liquid flow path. It has been found that thehollow jet of liquid is an effect manner for supplying air to the mixingchamber.

The air supply means may be passive. Optionally, the second nozzleincludes a venturi and is arranged for sucking air into the liquid flowpath when liquid flows through the second nozzle. In this way air issucked into the liquid flow path and transferred to the mixing chamberby the hollow jet of liquid formed at the first nozzle. Furthermore, thepassive air supply means help prevent back flow of the mixture in themixing chamber, as air is being sucked into the liquid flow path andsupplied into the mixing chamber.

Optionally, the air supply means comprise a first air supply valvearranged for selectively connecting the air supply duct to an airsupply, preferably to atmosphere. In this way, the amount of airtransported to the mixing chamber may be controlled. By controlling theamount of air entering the mixing chamber, the foam layer may becontrolled.

Optionally, the air supply means is active, for example, the air supplymeans further comprise an air pump arranged for actively supplying airto the liquid flow path via the air supply duct.

Optionally, the air supply means further comprise a second air supplyvalve arranged for selectively connecting the air pump to the air supplyduct. In this way air entering the system via the air pump can becontrolled.

Optionally, the first and/or second air supply valve is biased closed.In this way, the beverage preparation device is arranged for selectivelyopening the first and/or second air supply valve.

Optionally, the beverage preparation device is arranged for selectivelyopening the first air supply valve when the drive shaft is activated. Inthis way air is supplied to the mixing chamber at the same time thatbeverage related ingredient is being supplied for produced a beverageconsumption with a foam layer.

Optionally, the air supply duct includes a one way valve arranged toprevent liquid from traveling along the air supply duct. The one wayvalve prevents liquid from traveling up into the air supply duct. Thisprevents the air supply duct from being dirtied by mixture residue andprovides a system that is more hygienic.

Optionally, the beverage preparation device comprises flushing meansarranged for supplying a flushing fluid, and a flush valve arranged forselectively connecting the flushing means to the air supply duct,wherein the flush valve is located downstream from the one way valvesuch that flushing fluid supplied by the flushing means flows from theflush valve through the air supply duct into the liquid flow path andinto the mixing chamber. In this way a flushing liquid, such as water,can be cycled through a portion of the air flow path and a portion ofthe liquid flow path.

Optionally, the beverage preparation device is arranged for opening thefirst air valve and the flushing valve simultaneously.

Optionally, the beverage preparation device is arranged for activatingthe air pump and for opening the second air valve, for example at theend of a beverage cycle, for a period of 1-5 seconds. Activating the airpump may help flush out any residual liquid in the air flow path and/orliquid flow path. This may result in the system being more hygienic.

Optionally, the beverage preparation device is arranged for activatingthe air pump and opening the second air valve for a period ofsimultaneous to the activation of the drive shaft. In this way, abeverage having a foam layer may be produced. Actively supplying air, bymeans of an air pump, and controlling the air supply by means of thesecond air valve, while supplying a beverage related ingredient from theoutlet of the doser, may provide more control to the foaming process.

Optionally, the liquid supply means is arranged for supplying the liquidto the mixing chamber in a direction substantially tangential to avertical extent of the mixing chamber such that a liquid swirl iscreated in a mixing direction. In this way, a swirl is created in themixing chamber. It has been found that such a swirl promotes mixing andimproves foaming.

Optionally, an upstanding inner wall of the mixing chamber is providedwith an inlet for supplying liquid to the mixing chamber, and whereinadjacent to the inlet, in a direction opposite the mixing direction, aramp is provided for directing liquid swirling in the mixing chamberaway from the upstanding wall in the area of the inlet. In this wayliquid already in the mixing chamber is launched by the ramp over theliquid supply inlet. This helps prevent liquid from entering the inletand traveling up the liquid flow path. In this way contamination of theliquid flow path, and mixture residue buildup is prevented.Additionally, it has been found that by launching the mixture swirlingin the mixing chamber over the liquid supply inlet foaming is promoted.Without wishing to be bound by any theory, it is believed that the ramphelps reduce the centrifugal force at the inlet of the mixing chamber,which therefore reduces the back pressure at the inlet of the mixingchamber.

Also according to the invention a beverage preparation device isprovided for use with at least one exchangeable supply pack holding abeverage related ingredient. The beverage preparation device comprises amixing chamber having a beverage outlet, liquid supply means including aliquid flow path for supplying a liquid to the mixing chamber; airsupply means for supplying air to the liquid flow path, and a driveshaft. The beverage preparation device is mechanically connectable withat least one exchangeable supply pack. When the beverage preparationdevice is connected to the at least one exchangeable supply pack, themixing chamber of the beverage preparation device is in fluidcommunication with an outlet of the at least one exchangeable supplypack and the drive shaft of the beverage preparation device is arrangedfor transmitting torque from the beverage preparation device to the atleast one exchangeable supply pack. When the drive shaft is activated,beverage related ingredient is supplied from the outlet of theexchangeable supply pack into the mixing chamber.

Also according to the invention a method is provided for preparing abeverage, for example with the system according to the invention. Themethod includes the steps of providing a beverage preparation devicecomprising a mixing chamber having a beverage outlet and a drive shaft;providing at least one exchangeable supply pack holding a beveragerelated ingredient, wherein the at least one exchangeable supply packincludes a container for holding a beverage related ingredient, and adoser having an outlet, wherein the doser is arranged for supplying thebeverage related ingredient from the container to the outlet of thedoser in a dosed manner; mechanically connecting the at least oneexchangeable supply pack to the beverage preparation device such thatthe outlet of the doser is in fluid communication with the mixingchamber and the drive shaft is arranged for transmitting torque from thebeverage preparation device to the doser; supplying liquid to the mixingchamber; supplying air to the mixing chamber; and activating the driveshaft to supply beverage related ingredient to the mixing chamber.

Also according to the invention a beverage preparation unit is providedfor preparing beverage consumptions using a beverage related ingredient.The beverage preparation unit comprises a mixing chamber having abeverage outlet, a liquid flow path for supplying a liquid to the mixingchamber, and an air flow path for supplying air to the liquid flow path.The mixing chamber is arranged for receiving a beverage relatedingredient, such as concentrate, preferably from an exchangeable supplypack. Optionally, the liquid flow path is arranged for generating ahollow jet of liquid having an outer liquid portion extending in a flowdirection of the jet and an inner air portion extending in a flowdirection of the jet wherein the outer liquid portion surrounds theinner air portion. It will be appreciated that features discussed abovemay be included in the unit.

Optionally, where the liquid flow path enters the mixing chamber, themixing chamber has a diameter in the range of 5 mm-100 mm, preferably 5mm-50 mm, and more preferably 10 mm-20 mm. The diameter is preferablymeasured at the middle of the liquid flow path where the liquid flowpath enters the mixing chamber, for example in the form of an inlet. Itwill be appreciated that if a ramp is present in the mixing chamber thediameter of the mixing chamber is measured as if the ramp was notpresent. As the mixing chamber preferably tapers the diameter measuredin the vicinity above where the liquid flow path enters the mixingchamber may be different from the diameter in the vicinity below wherethe liquid flow path enters the mixing chamber. However these diameterspreferably also fall within the given range.

Also according to the invention a beverage preparation unit incombination with a pump is provided.

Also according to the invention a beverage preparation unit incombination with an air pump is provided. The air flow path of the unitis arranged to be in fluid communication with the air pump. Optionally,the air pump is arranged for supplying air to the air flow path at apressure in the range of 0.05 bar-10 bar, preferably 0.1 bar-0.3 bar,and most preferably 0.1 bar-0.2 bar. Optionally, the air pump is one ofa membrane pump, a positive displacement pump, and a gear pump.Optionally, the air pump is arranged to be powered by direct current.Optionally, the air pump is arranged to be powered by alternatingcurrent.

Also according to the invention a beverage preparation unit incombination with an liquid pump, such as a water pump, is provided. Theliquid flow path of the unit is arranged to be in fluid communicationwith the liquid pump. Optionally, the liquid pump is arranged forsupplying liquid to the liquid flow path at a pressure in the range of0.5 bar-15 bar, preferably 1 bar-7 bar, and most preferably 1.5 bar-3bar. Optionally, the liquid pump is one of an oscillating piston pump, agear pump, and a positive displacement pump. Optionally, the liquid pumpis arranged to be powered by direct current. Optionally, the liquid pumpis arranged to be powered by alternating current.

Also according to the invention a beverage preparation unit incombination with liquid conditioning unit is provided. The liquid flowpath of the unit is arranged to be in fluid communication with theliquid conditioning unit. Optionally, the liquid conditioning unit isarranged to heat and/or cool liquid, such as water, to be supplied tothe liquid flow path to a temperature in the range of 2-100 degreesCelsius, preferably 5-80 degrees Celsius. Optionally, the liquidconditioning unit has a volume of 100 mL-20000 mL, preferably a volumeof 5000 mL-10000 mL.

Optionally, the liquid conditioning unit is a boiler and is arranged forheating liquid, such as water, to be supplied to the liquid flow path toa temperature in the ranges of 50-100 degrees Celsius, preferably 60-90degrees Celsius, and most preferably 70-80 degrees Celsius.

Optionally, the liquid conditioning unit is a cooler and is arranged forcooling liquid, such as water, to be supplied to the liquid flow path toa temperature in the ranges of 2-20 degrees Celsius, preferably 5-15degrees Celsius, and most preferably 5-10 degrees Celsius.

Optionally, the liquid conditioning unit includes a boiler and/or acooler.

Also according to the invention a beverage preparation unit incombination with at least one of a pump, an air pump, a liquid pump, anda liquid conditioning unit is provided. The at least one pump, air pump,liquid pump, and liquid conditioning unit optionally being such asdescribe above.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further elucidated by means of non-limitingexamples referring to the drawings, in which

FIG. 1 shows a perspective view of a beverage preparation deviceconnected to a doser of an exchangeable pack of a system according tothe invention;

FIG. 2A shows a schematic view of an exchangeable pack of a systemaccording to the invention;

FIG. 2B shows a schematic cross-section view of the doser of theexchangeable pack of FIG. 2A;

FIG. 3 shows a cut-away view of the mechanical connection between theexchangeable pack and the beverage preparation device of a systemaccording to the invention

FIG. 4 shows an exploded perspective view of a doser of an exchangeablepack of a system according to the invention;

FIG. 5 shows a side plan view of a beverage preparation device of asystem according to the invention;

FIG. 6 shows a perspective cut-away view of a beverage preparationdevice of a system according to the invention;

FIG. 7 shows simulated view of a beverage preparation device of a systemaccording to the invention;

FIG. 8 shows a top plan view of a beverage preparation device of asystem according to the invention;

FIG. 9 shows a side plan view of a beverage preparation device of asystem according to the invention;

FIG. 10 shows a side plan view of an example of a beverage preparationdevice of a system according to the invention;

FIG. 11 shows a schematic diagram of a beverage preparation device of asystem according to the invention;

FIG. 12 shows a side plan view of a selection valve provided in abeverage preparation machine in a first functional position;

FIGS. 13A-13E show perspective views of the different functionalpositions of the valve shown in FIG. 12;

FIG. 14 shows an exploded perspective view of a beverage preparationunit according to the invention; and

FIG. 15 shows a perspective view of a beverage preparation device forpreparing beverage consumptions in accordance with the invention.

DETAILED DESCRIPTION

The same reference numerals are used for features appearing in multipleFigures. The system 1 for preparing beverage consumptions comprises abeverage preparation device 2, and at least one exchangeable supply pack4 arranged for holding a beverage related ingredient. FIG. 1 shows thesystem 1 for preparing beverage consumptions. In FIG. 1, a beveragepreparation device 2 and a doser 6 of an exchangeable supply pack areshown. The exchangeable supply pack 4 is shown in FIG. 2A. Theexchangeable supply pack includes a container 5 holding a beveragerelated ingredient, such as concentrate. The beverage preparation device2 comprises a mixing chamber 8 having a beverage outlet 10. In thisexample, the mixing chamber 8 has a volume of about 4.5 ml. The mixingchamber tapers outwardly in an upward direction towards the top of themixing chamber, see FIG. 9. The, liquid supply means 12 detailed inFIGS. 5 and 6 is arranged for supplying a liquid, in this example waterunder pressure, to the mixing chamber 8, via inlet 16. As shown in FIG.9, the mixing chamber has a diameter DM, in this example 15 mm, wherethe liquid flow path enters the mixing chamber. In this example theliquid flow path enters through inlet 16. The air supply means 18,detailed in FIG. 6, is arranged for supplying air to the liquid flowpath 14. The beverage preparation device also comprises a drive shaft20. The doser 6, explained later in detail with regard to FIG. 4, has anoutlet 22. The doser 6 is arranged for supplying beverage relatedingredient, in this example concentrate, from the container 5 to theoutlet 22 of the doser 6 in a dosed manner.

The at least one exchangeable supply pack 4 and the beverage preparationdevice 2 are mechanically connectable. The mechanical connection isshown in FIG. 3. In this example, the mechanical connection is made bythe drive shaft 20 to the doser 6.

As seen in FIGS. 1 and 3, when connected the outlet 22 of the doser 6 isbrought in fluid communication with the mixing chamber 8 through anopening 26 in the top of the mixing chamber and the drive shaft 20 ofthe beverage preparation device 2 is arranged for transmitting torquefrom the beverage preparation device to the doser 6 such that when thedrive shaft 20 is activated beverage related ingredient, in this exampleconcentrate is supplied from the outlet 22 of the doser 6 into themixing chamber 8. The functional height H of the mixing chamber is shownin FIG. 1. In this example the functional height H is 20 mm.

The doser 6 is attached to one side of the exchangeable supply pack 5and includes a pump assembly 61. The pump assembly 61 enables thepumping of a desired dosage of the ingredient from the container 5 tothe beverage dispensing device. Prior to use of the exchangeable supplypack 4, the doser 6 may be protected by a protective part 7 visible inFIG. 2A.

In FIG. 2B, which illustrates a cross section of the exchangeable supplypack 5 including the doser 6, it can be seen how the doser 6 is attachedto the exchangeable supply pack 4. The doser 6 comprises a top cap 62including an adapter 63 which is inserted into a spout 64 that is fixedwith the container 5 of the pack 4. Inside the container 5, the spout 64is attached by means of a spout ring 66.

The spout 64 of the exchangeable supply pack 4 may be shapedcorrespondingly with the adapter 63 such as to fix the adapter andtherewith the doser 6 to the exchangeable supply pack 4. Additionally,the spout may further be shaped to seal the connection between the spout64 and the adapter 63 such as to prevent leakage of the ingredient outof the container 5 in use.

The doser 6 includes a pump channel 67 which is formed by a pump housing68 and a bottom housing 69. The pump housing 68 and the bottom housing69 may be correspondingly shaped such as to enable engagement therebetween for forming the pump channel 67. The pump channel at leastincludes a pump chamber 70 (see FIG. 4) which includes a gear pump 16.Using the gear pump 71, the ingredient is transported from the container5 to an outlet 22 of the doser 6.

FIG. 4 provides an exploded view of a doser 6. Visible in FIG. 4 are theadapter 63, the pump housing 68, and the bottom housing 69 of the doser6. The pump chamber 70 includes two mutually engaging gears 13 and 18.The gears 72 and 73 are located in the pump chamber 70 closely fittingtherewith, such as to provide the gear pump 71. The gear pump 71 can beoperated by operating the driving gear 72, which in turn will drive thedriven gear 73 in counter rotation. Because the teeth of the gears 72and 73 move closely past the inside of the walls of the pump chamber 70,the fluid is pumped from the inlet channel 74 to the outlet channel 75of the pump channel 67. The driving gear 72 comprises a shaft opening 80for receiving the drive shaft 20 of the beverage preparation device foroperating the gear pump.

In the assembled state the fluid is received through the inlet 76 at theopen end of the adapter 63, and will flow to the interior of the bottomhousing 69 of the assembly. From there, it will further flow into theinlet channel 74 until it reaches the pump chamber 70. When the gearpump is operated by the drive shaft, ingredient is transported by thegears 72 and 73 to the outlet channel 75 towards the outlet 22. Near theoutlet 22, the doser further includes seal 77 for providing of theingredient to the beverage dispensing machine. The doser 6 furtherincludes a valve 24 arranged in the outlet 22 for closing the doser,e.g. when not in use or when the mixing chamber 8 is being rinsed toprevent bacterial growth.

In between the driving gear 72 and the support wall 79 being formedintegrally with the bottom housing 69, a flexible seal 78 is present toprevent leakage. The flexible seal 78 for example seals the connectionbetween the pump housing 68 and the bottom housing 69 forming thepumping channel and pumping chamber. The flexible seal 78 furthercooperates within the pumping assembly such as to prevent leakage alongthe drive shaft 20 that will drive the driving gear 72. The flexibleseal extends underneath and beyond the side walls of the pump channel 67formed by pump housing 68 for at least a part of the periphery of thepumping chamber 70 and optionally also the outlet channel 75, such thatthe seal 78 is fixed in between the pump housing 68 and the bottomhousing 69. The flexible seal 78 comprises a through opening 81coinciding with the shaft opening 80 and the axle reception opening forreceiving the driving shaft.

The outlet 22 of the doser 6 is closed off by the one way valve 24. Thevalve 24 is biased closed in order to seal off the doser outlet 22 whennot in use. When the gear pump is driven by the drive shaft 20, the gearpump pumps concentrate towards the outlet 22 of the doser 6 driven thegear pump. The pump assembly pumps concentrate towards the outlet 22 ofthe doser 6. When the bias of the one way valve 24 is overcome,concentrate flows with help from the gear pump and the influence ofgravity into the mixing chamber 8.

In this example, when driven by the drive shaft 20 of the beveragepreparation device 2, the doser 6 is arranged for supplying concentrateto the mixing chamber 8 at a rate of 0-7 ml/sec. This range enables thesystem 1 to produce a wide range of beverages, for example espresso,lungo, cappuccino, etc.

The liquid supply means 12 is arranged for generating a hollow jet ofliquid, in this example water, and for supplying the hollow jet into themixing chamber 8 through the inlet 16. The liquid flow path 14 includesa first nozzle 34 arranged for creating a hollow jet of water. Thehollow jet of water has an outer liquid portion and an inner airportion.

The first nozzle 34 tapers towards the mixing chamber 8 and terminatesthe inlet 16 in a sidewall 36 of the mixing chamber 8. The liquid flowpath 14 comprises a second nozzle 38 located upstream from the firstnozzle 34 and arranged for generating a substantially solid jet ofliquid.

Hot water is supplied under pressure to the second nozzle 38. Thereforethe liquid supply means 12 further includes a water reservoir 28, awater pump 30 and a water heater 32. An intermediate portion 40separates the first nozzle 34 and the second nozzle 38. In this examplethe intermediate portion 40 is tubular. Air flow is possible around thesubstantially solid jet in the intermediate portion.

The intermediate portion 40 is connected to air supply means 18, shownin FIG. 6, which in this example, include an air duct 42 which is influid communication with the liquid flow path 14. The air duct islocated upstream from the first nozzle 34 and downstream from the secondnozzle 38. The air duct 42 is connected to a first air supply valve 44arranged for selectively connecting the air supply duct 42 to an airsupply to the ambient air. The second nozzle 38 includes a venturi influid communication with the intermediate portion 40 and therefore influid communication with ambient air when the first air supply valve 44is open. When the liquid supply means 12 are activated and water flowsthrough the second nozzle, air is sucked into the liquid supply path bythe venturi of the second nozzle. The air supply means 18 are passive.

As the substantially solid jet of water travels from the second nozzle38 to the first nozzle 34, it does not contact an inner surface of theintermediate portion 40. Therefore air flow around the substantiallysolid jet of water is possible.

The nozzles 34, 38 are positioned relative to each other such that thesubstantially solid jet of liquid impacts an inner surface 46 of thefirst nozzle 34 in an impact zone 48. As shown in FIG. 7, this causesthe jet to swirl around the inner surface 46 of the first nozzle 34. Theliquid of the substantially solid jet is directed outwardly and the airsurrounding the substantially solid jet of liquid, in the intermediateportion 40, is directed inwardly, thereby forming a hollow jet of water.It is noted that the second nozzle 38 is positioned such that thesubstantially solid jet is off-centered with respect to a center of thefirst nozzle. This is best seen in of FIG. 7.

When generated, the outer water portion of the jet sealingly contactssubstantially the entire inner surface 46 of the nozzle 34 in an area 50directly adjacent to the inlet 16 to the mixing chamber 8. In this waythe mixture mixing in the mixing chamber is prevented from exiting themixing chamber 8 through the inlet 16 and into the first nozzle 34 ofthe liquid flow path 14. The prevents mixture residue from forming inthe liquid flow path 14 and may improve overall hygiene of the system.

In this example, the first nozzle 34 is stationary and the second nozzle38 is movable relative to the first nozzle, in a direction D. Inparticular, the first and second nozzle 34, 38 are relatively movablebetween a first and a second position. In the first position, shown inFIG. 6, the first and second nozzle 34, 38 are positioned relative toeach other such that the substantially solid jet is off-centered withrespect to a center of the first nozzle. In the second position thefirst ands second nozzle 34, 38 are positioned relative to each othersuch that the substantially solid jet of liquid is centered with respectto a center of the first nozzle. As described above, in the firstposition, the liquid supply means 12 is arranged for supplying a hollowjet into the mixing chamber 8. In the second position, the liquid supplymeans is arranged for supplying a substantially solid jet of liquid tothe mixing chamber 8. When the liquid supply means 12 supplies asubstantially solid jet of liquid, the liquid of the jet also sealinglycontacts substantially the entire inner surface 46 of the nozzle 38 inan area 50 directly adjacent to the inlet 16 to the mixing chamber 8. Inthis way, the mixture in the mixing chamber 8 is prevented from flowingout of the mixing chamber 8 and into the liquid flow path 14.

As seen from FIG. 8, the liquid supply means 12 and the liquid flow path14 supply water to the mixing chamber in a direction substantiallytangential to a vertical extent A of the mixing chamber 8. In this way,when water is supplied to the mixing chamber 8, a swirl of mixture iscreated in a mixing direction B. This helps better mix the concentrateand water in the mixing chamber. In addition, the swirl promotes foamingof the mixture. In this way beverage consumptions with a foam layer canbe produced. Adjacent to the inlet 16, in a direction opposite themixing direction B, a ramp 52 is provided. The ramp 52 directs themixture swirling in the mixing chamber 8 for directing liquid swirlingin the mixing chamber away from the upstanding wall, sidewall 36, in thearea of the inlet 16. Directing the mixture away from the sidewall 3helps prevent the mixture from exiting the mixing chamber 8 andtraveling up the liquid flow path 14. In this way, mixture residuebuildup in the liquid flow path is reduced. Additionally, it is believedthat by launching the mixture swirling in the mixing chamber 8, by meansof the ramp 52, over the liquid supply inlet 16 foaming is promoted. Itis believed that the ramp 52 helps reduce the back pressure at the inlet16 of the mixing chamber 8.

In this example, the air supply means 18 further comprise an air pump 54arranged for actively supplying air to the liquid flow path 14 via theair supply duct 42. The air pump 54 is connected to the air duct 42 by asecond air supply valve 56. Both the first and second air supply valves44 and 56 are biased closed.

In this example, the beverage preparation device 2 comprises flushingmeans 58 for supplying a flushing fluid, in this example water, to theair supply duct 42. The air supply duct 42 includes a one way valve 60,which prevents flushing water from traveling along the air supply duct42. As shown in FIG. 6, the flushing means 58 is connected to the airduct 42 at T-junction. The flushing means 58 is located downstream fromthe one way valve 60 such that flushing fluid, in this example water,supplied by the flushing means 58 flows through the air supply duct 42into the liquid flow path 14 and into the mixing chamber 8. Typically,the flushing means 58 include a flush valve arranged for selectivelyconnecting the flushing means 58 to the air supply duct 42.

FIG. 10 show another example of a configuration for generating a hollowjet to be injected into the mixing chamber 8. This embodiment can beapplied n each of the other embodiments discussed. In the embodiment asshown in FIG. 10 the supply pack 4 of a type as discussed for the otherembodiments can be connected with the mixing chamber 8 on top of themixing chamber. The liquid flow path 14 includes a first nozzle 34 andthe liquid flow path 14 is arranged for generating a hollow jet ofliquid having an outer liquid portion 100 extending in a flow direction,F, of the jet and an inner air portion 101 extending in a flowdirection, F, of the jet wherein the outer liquid portion 100 surroundsthe inner air portion 101. In this way the hollow jet has the form of astraw wherein the inner side of the straw represents the inner airportion 101 of the jet and the straw itself represents the outer liquidportion of the jet 102. Thus the hollow jet in fact is a combination ofan jet of air and a hollow jet of liquid which surrounds the jet of air.The flow direction of the jet of air and the flow direction of thehollow jet of liquid is the same direction F.

In this example the jet which is generated extends in an axial directionA′ of the jet, wherein the system is further provided with air injectionmeans 102 for generating a flow of air and injecting the flow of airsubstantially coaxially in the jet. The flow direction of the jet is thesame as the flow direction of the flow of air 104 so as to obtain thehollow jet.

In other words it holds that the flow of liquid in the liquid flow path14 extends in an axial direction A′ wherein the system is furtherprovided with air injection means 102 for generating a flow of air whichextends in the axial direction A′ and for injecting the flow of airsubstantially coaxially in the flow of liquid in the liquid flow path 14wherein the flow direction of the flow of liquid in the liquid flow path14 is the same as the flow direction of the flow of air so as to obtainthe hollow jet.

In this example, the liquid flow path 14 includes the first nozzle 34which is arranged for generating a hollow jet of liquid. The airinjection means comprise a needle 106 having an open end 108. The axialdirection of the needle and an the axial direction of the jet at leastsubstantially coincide, as shown in FIG. 10. The length of a portion ofthe needle extending in the axial direction in the liquid flow path isindicated by L1 and is 9 mm. The open end 108 of the needle 106 islocated in the nozzle 34, downstream from the entrance opening 110 ofthe nozzle 34. In this example, the open end 108 of the needle iscentered in the axial extent of the nozzle 34. In this way the flow ofair is injected into the center of the jet. The air injection meansfurther include an air pump 112 and an air valve 114 for selectivelygenerating a stream of air that is supplied to the needle 106 through anair channel 116 for generating a flow of air (which may for example bealso described as an jet of air).

Thus in the center of the water jet a needle 106 with a certain lengthis placed. Typically, the needle 106 has an inside diameter of 0.2 mm.

With help of an speed regulated air pump, a flow of air (which may forexample be also described as an jet of air) is pumped through theneedle. Surrounding the needle 106, a flow of pressurized water iscreated. This configuration takes care to create a straight beam, i.e.not divergent and not converging. The air is protected from theunder-pressure in the channel by the water jet.

In this way air is actively supplied by the hollow jet to the mixingchamber. In use the air injection means 102 is activated when the liquidsupply means 12 is activated for supplying liquid, in this examplewater, to the liquid flow path 14.

In another embodiment the open end of the needle lays upstream of thenozzle 34 for example on a position indicated with arrow P. In that casethe flow of air (which may for example be also described as an jet ofair) can penetrate into and displace the liquid flow in the nozzle sothat a hollow jet is formed.

In another embodiment the open end of the needle lays downstream of thenozzle 34 for example on a position indicated with arrow Q. In that casethe flow of air (which may for example be also described as an jet ofair) can penetrate into and displace the liquid flow downstream of thenozzle so that a hollow jet is formed. Other ways of injecting a jet ofair in about the middle of a stream of water for generating a hollow jetalso form part of the present invention.

In FIG. 12 the length L2 of a portion of the needle extending along theaxial direction of the liquid flow path coaxially with the liquid flowis 4 mm.

It will be appreciated that this example of the liquid flow path 14arranged for generating a hollow jet of liquid may be advantageouslyintegrated into a selection valve 201. Such a multi-functional valvereduces the number of valves needed in the beverage preparation device.

FIG. 11 shows a schematic diagram of an example of a beveragepreparation device of a system according to the invention. It will beappreciated that a selection valve 201 and a mixing chamber 208 may forma beverage preparation unit 200. A beverage preparation device, such asthe one schematically depicted in FIG. 11, may be provided with aplurality of beverage preparation units 200. The unit is preferablyarranged to cooperate with an exchangeable supply pack, for example whenthe exchangeable supply pack is connected with the beverage preparationunit, an outlet of the doser is brought in fluid communication with themixing chamber. The unit may also include a doser interface forinteracting with a supply pack for dosing beverage related ingredientinto the mixing chamber. Additionally, the unit may include an actuator,such as a stepper motor, for controlling the selection valve 201.

In FIG. 11, the inputs and output of the selector valve 201 are shown.Hot water inlet 202 is connected to the water heater 32 which is in turnis connected to a water flow meter 234, a water pump 230 and a waterreservoir 228. The air pump 212 is connected via air inlet 204 to theselection valve 201. Outlet 206 of the valve 201 is connected to themixing chamber 208 via a connection line 211. The selection valve 201also has a bypass outlet 214 which is connected to the water reservoir228 via a bypass connection line 216. It is noted that the water heater232 is connected to the water reservoir 228 by a pressure relief valve220 and connection line 218. It will be appreciated that a supply packof a type as discussed for the other embodiments can be connected withthe mixing chamber 208 on top of the mixing chamber. Although notdepicted in FIG. 11, the beverage preparation device 2 may include adoser driving interface for interacting with the supply pack to dosebeverage related ingredient into the mixing chamber 208. An example of adoser has been discussed for the other embodiments. The mixing chamber208 also has a beverage outlet 210.

A side plan view of the selection valve 201 is shown in FIG. 12. Thevalve 201 includes five ceramic elements 241-245. Elements 241 and 245are fixed within a valve body 240. The valve body 240 is shownschematically in FIG. 12. Element 241 includes the hot water inlet 202,air inlet 204, and bypass outlet 214. Element 245 includes the outlet206. A selector member 250, which is movably mounted with respect to thevalve body 240, is formed by elements 242 and 243 mounted within an arm248. The selector member 250 is driven, in this this example, by astepper motor. In this example the selector member 250 is slidablymounted with respect to the valve body 240.

Element 244 is a satellite element associated with the selector member250. The satellite element, element 244, has a predefined limited amountof free relative movement with respect to the selector member forallowing the satellite element 244 to be positioned independently of theselector member. In this way, the valve may be placed in differentfunctional positions by the driving the selector member 250. Schematicperspective views of the different functional positions of the valve 201are shown in FIGS. 13A-13E. Thus the selector member 250 and thesatellite element 244 are movable in a plane substantially perpendicularto axial direction A′, and preferably rotatable in the plane. Theelements slide over each other.

The configuration for generating a hollow jet to be injected into themixing chamber, as for example depicted in FIG. 10, may be integratedinto the valve 201. The functional position of valve 201 shown in FIG.12 generates a hollow jet to be injected into the mixing chamber 208.The liquid flow path 314, formed through the five elements 241-245,includes a first nozzle 334 located in element 244.

In this example the nozzle 334 has a tapered geometry wherein over theflow direction of the nozzle, the opening of the nozzle decreasesexponentially as shown in FIG. 13A. This allows for a suitable hollowjet to be formed with at a relatively low water pressure, for example awater pressure of 1.5-1.7 bar and preferably a water pressure of 1.3-1.4bar. This may permit the size and/or cost of the water pump to bereduced. Reducing the water pressure needed for form a suitable jet alsoreduces the pressure applied to elements 241-245. Thus in turn the powerneeded to drive the selector member 250 is also reduced. This may allowa smaller stepper motor to be used from operating the valve 201.

The air supply means in this example are active and include airinjection means. As shown in FIG. 11, air inlet 204 is connected to airpump 212. The air supply means further comprise a needle 306 having anopen end 308. The needle is provided in element 243 of the selectormember 250. The needle has an inner diameter of 0.26 mm and an outerdiameter C of 0.46 mm. In this embodiment, the needle 306 lays upstreamof the nozzle 334. In this way the flow of air (which may for example bealso described as an jet of air) can penetrate into and displace theliquid flow downstream of the nozzle 334 so that a hollow jet is formed.Surrounding the needle 306, a flow of pressurized water is created. Theair pump 212 is a diaphragm pump and is arranged to keeps the needle 306under a constant overpressure of 0.2-0.3 bar. The prevents water fromentering the air supply means.

As can be seen in FIG. 12, the axial direction of the needle 306 and anthe axial direction of the nozzle 334 and thus the axial direction A′ ofthe jet at least substantially coincide. In this example, the open end308 of the needle is centered in the axial extent of the nozzle 334. Inthis way the flow of air is injected into the center of the jet, inother words air is injected substantially coaxially in the jet. The flowdirection of the jet is the same as the flow direction of the flow ofair so as to obtain the hollow jet. This configuration takes care tocreate a straight beam, i.e. not divergent and not converging.

Thus the liquid flow path 314 is arranged for generating a hollow jet ofliquid having an outer liquid portion 400 extending in a flow direction,F, of the jet and an inner air portion 401 extending in a flowdirection, F, of the jet wherein the outer liquid portion 400 surroundsthe inner air portion 401. In this way the hollow jet has the form of astraw wherein the inner side of the straw represents the inner airportion 401 of the jet and the straw itself represents the outer liquidportion of the jet 400. Thus the hollow jet in fact is a combination ofan jet of air and a hollow jet of liquid which surrounds the jet of air.The air is protected from the under-pressure in the channel by the waterjet. The flow direction of the jet of air and the flow direction of thehollow jet of liquid is the same direction F. The hollow jet exitsthrough outlet 206 of the valve 201. The outlet 206 of valve 201 has alarger diameter D, in this example 5 mm, than the diameter d of thehollow jet, in this example approximately 0.95 mm. In this way thehollow jet does not contact the inner surface of connection line 211connecting the outlet 206 to the mixing chamber 208.

In this example, the additional air valve for selectively generating astream of air that is supplied to the needle 306 is incorporated intothe valve 250. This function is incorporated into the valve 250 throughthe relative positions of the selector element 250 and the fixed element241 (see FIGS. 13B-13E). In this functional positions, the element 243and thus needle 306 is no longer in the liquid flow path 314.

In FIGS. 13A-13E, the valve body 240 and arm 248 have been omitted forclarity in order to show the different functional positions. In thesepositions different inlets and outlets are brought in fluidcommunication with each other. In FIG. 13A, a perspective view of theselection valve 201 in the functional position for generating a hollowjet is shown. In this position, both the hot water inlet 202 and airinlet 204 are in fluid communication with the outlet 206. This positionis ideal for producing foamed beverages, for example coffee with a layerof crema.

In FIG. 13B, the valve is in a closed off but vented position. Neitherthe hot water inlet 202 nor the air inlet 204 are in fluid communicationwith the outlet 206. Flow from these inlets is blocked by element 242which has been moved relatively to element 241. The outlet 206 ishowever in this position vented through vent 260 provided in element244. In this position, due to the vent, the mixing chamber drainsitself.

In FIG. 13C, the valve closed off. In this functional position, which issimilar to the position shown in FIG. 13B, the neither the hot waterinlet 202 nor the air inlet 204 are in fluid communication with theoutlet 206. Both are blocked by the element 242 which has been movedrelatively to element 241. In this position, the outlet 206 is notvented. Such a position is useful when a plurality of valves and mixingchambers are used. In an embodiment wherein a beverage preparationdevice is provided with a plurality of beverage preparation units, forexample one unit for a coffee related beverage ingredient and anotherunit for a milk related beverage ingredient, the functional positionshown in FIG. 13C is useful. When the valve 201 of the beveragepreparation unit is in the closed position the water pressure of thedevice may be maintained.

In FIG. 13D, a perspective view of the selection valve 201 in a bypassposition is shown. In this functional position, the air flow is from airinlet 206 is blocked off by element 242. Hot water inlet 202 is in fluidcommunication with bypass outlet 214 via a channel 262 provided inelement 242. This position is useful for preventing boiler pressurebuildup and to allow removal of air from the boiler at the beginning ofthe drink production process.

In FIG. 13E air flow at air inlet 204 is blocked by element 242. Theflow to the bypass outlet 214 is also blocked by element 242. The hotwater inlet 202 is brought in fluid communication with the outlet 206 byopenings 264, 266, and 268 in elements 242, 243, and 244 respectively.These openings 264, 266, and 268 have substantially the same diameter asthat of outlet 206. Thus a channel with a diameter of approximately 5 mmis formed by the relative positions of the elements connecting the hotwater inlet 202 to the outlet 206. This functional position is ideal forproducing foamless beverages, such as brewed coffee.

It will be appreciated that when element 243 is positioned relative tothe other elements such that needle 306 is not in the liquid flow path314 the needle is protected. It is further noted that relative movementof element 244 with respect to elements 243 and/or 245 may help removelimestone deposit built up on the needle 306 and/or opening 266 ofelement 243 as well as limestone deposit built up on the nozzle 334and/or opening 268 of element 244.

An example of a beverage preparation unit is shown in FIG. 14. Thebeverage preparation unit 200 shown in FIG. 14 includes a selectionvalve 201 and mixing chamber 208. In addition, unit 200 also includes astepper motor 280 for controlling the selection valve 201 between thedifferent functional positions. The unit 200, in this example, isfurther provided with a doser interface, drive shaft 290. The doserinterface is driven by stepper motor 292. The doser interface isarranged to interact with an exchangeable supply pack as described withregard to the other examples. The doser interface, in this example driveshaft 290, may be mechanically connectable with a doser of anexchangeable supply pack. The at least one exchangeable supply packincludes a container for holding a beverage related ingredient, and adoser outlet. The doser is arranged for supplying the beverage relatedingredient from the container to the outlet of the doser in a dosedmanner. When the exchangeable supply pack is connected to the beveragepreparation unit 200, the outlet of the doser is brought in fluidcommunication with the mixing chamber, preferably via an opening in thetop of the mixing chamber 208. When the drive shaft 290 of the beveragepreparation device is beverage related ingredient is supplied from theoutlet of the doser into the mixing chamber. The mixing chamber 208 isprovided with outlet 210.

It will be understood that the beverage preparation machine shown inFIG. 11 may be operated in a similar manner as described for otherembodiments of the invention. Furthermore it will be appreciated thatthe beverage preparation unit provided in the beverage preparationdevice shown in FIG. 11 may be arranged to cooperate with anexchangeable supply pack.

The system 1 comprises a beverage preparation device 2, which in turncomprises a beverage preparation unit for example, unit 200. As shown inFIG. 15, the beverage device 2 includes an exchangeable supply packcompartment for receiving an exchangeable supply pack with beveragerelated ingredients. The compartment is closed by a front hatch 15,which can be opened to give access to the compartment. The beveragepreparation device 2 further comprises a housing 9. Additionally, thebeverage preparation device 2 may be further provided with a drip tray11. The drip tray may be provided in a pedestal of the device 2. Apartfrom the features described herein above, the device 2 includes at leastone mixing chamber 8 for mixing, e.g., concentrated liquid coffee ormilk ingredients with hot water for dispensing through either a coffeeoutlet 120 or a milk outlet 121.

An example beverage cycle for producing will now be described. During abeverage cycle, the beverage preparation device 2 is arranged foractivating the liquid supply means 12 for a first period of time and foractivating the drive shaft 20 for a second period of time for supplyingconcentrate to the mixing chamber 8. In this example the first andsecond period are continuous. In other words the liquid supply means 12is activated for the entire first period, and the drive shaft 20 isactivated for the entire second period.

In this example, the liquid supply means 12 are activated before thedrive shaft 20. The second period starts 0.25 seconds after the firstperiod. In the first period, the liquid supply means 12 supplies waterto the mixing chamber on average with 10 ml/sec. The second nozzle 38generates a jet of liquid having a stable speed of 14 m/sec. Thereforethe device doses liquid in the form of a jet having an average speed ofV. In this example V is 14 m/sec. As the device doses liquid into themixing chamber with Q ml/sec, the speed of the jet is Q/E m/sec. E isthe cross-surface area of the liquid of the jet in mm². In this example,E is 0.714 mm². At the beginning of the first period, the first airsupply valve 44 is opened. Therefore when the substantially solid jetimpacts the first nozzle 34 in the impact zone 48 and is directedoutwardly, air in the intermediate portion 40 is sucked in through theair duct 42 and one way valve 60 as the hollow jet is formed. The hollowjet spouts into the mixing chamber 8 via the inlet 16 in the sidewall 36of the mixing chamber creating a swirl. During the first period thedevice doses Z ml of liquid, in this example Z is 104.4 ml of liquid,for the one beverage, into the mixing chamber. The first period lasts10.4 seconds. Therefore the device doses liquid to the mixing chamberfor the preparation of one beverage during G seconds, and in thisexample G is 10.4.

At the start of the second period the drive shaft 20 is activated. Aftera ramp up phase, the drive shaft 20 rotates at substantially X RPMs, inthis example X is 190 revolutions per minute. The drive shaft transmits0.25 Nm of torque to the gear pump of the doser 6. As the gear pumpbegins to rotate, concentrate is pumped towards the outlet 22 of thedoser 6. The bias of the one way valve 24 is over come and concentrateis supplied to the mixing chamber 8 via the opening 26 with the help ofgravity. The doser, in this example, is arranged for dosing 0.198 ml perdrive shaft revolution. Therefore when the drive shaft rotates at Xrevolutions per minute, the doser doses the beverage related ingredienton average with C*X/60 ml/sec. In this example, X is 190 RPM and C is0.198 ml/rev, and therefore the doser doses the beverage relatedingredient on average with (0.198 ml/rev*190 RPM)/60, or 0.62 ml/sec.Therefore the beverage preparation device doses liquid is dosed to themixing chamber on average with Q ml/sec, in this example 10 ml/sec, andthe system doses ingredient for the preparation of the one beverage, onaverage with R ml/sec. In this example R is 0.62 ml/sec, as calculatedabove.

The second period lasts approximately 9.2 seconds. During the secondperiod 5.7 ml of concentrate are supplied to the mixing chamber 8.Therefore the device doses Z ml of liquid for one beverage into themixing chamber, and the system doses Y ml of beverage related ingredientinto the mixing chamber for the preparation of the one beverage. In thisexample, Z is 104.4 ml and Y is 5.7 ml.

Therefore when the device doses Z ml of liquid into the mixing chamberfor the one beverage, the system doses D*Z ml of beverage relatedingredient into the mixing chamber for the preparation of one beverage.In this example, Z is 104.4 ml of liquid and D is 0.0555. Thisrelationship produces a beverage with the desired strength and flavor.Additionally, as noted above, in the first period, the liquid supplymeans 12 supplies water to the mixing chamber on average with 10 ml/sec.Therefore the device doses liquid to the mixing chamber on average withQ ml/sec, in this example 10 ml/sec, and the system doses beveragerelated ingredient on average with F*Q ml/sec. In this example, thedoser doses the beverage related ingredient on average with 0.198ml/rev*190 rmp, or 0.62 ml/sec, therefore, in this example, F is 0.062.This relationship between the flow rates of the water and concentrateproduces a beverage with the desired strength and flavor.

In this example of a beverage cycle, the first air supply valve 44 isclosed part way through the first and second period. This is necessaryin order to control the amount of air entering the mixing chamber 8 andin turn to control the resulting foam layer.

The first period of activation of the liquid supply means 12 lasts 10.4seconds. Therefore the first and second period substantially overlap. Inother words water and concentrate are supplied simultaneously. However,the second period ends 0.95 second before the first period ends. In thisway, the liquid supply means 12 are active 0.95 seconds longer than thedrive shaft 20. This helps reduce mixture residue in the mixing chamber.In this 0.95 seconds, at the end of the beverage cycle, approximately,10 ml of water is supplied to the mixing chamber 8 by the liquid supplymeans 12. As the mixing chamber has a volume of approximately 4.5 mlthis causes the mixing chamber 8 to fill with swirling water. Due to theoutwardly extending sidewall 36 towards the top of the mixing chamberswirling water contacts the underside of the outlet 22 of the doser 6and the one way valve of the doser 24. This helps rinse away anyconcentrate present on these components. The water than leaves themixing chamber 8 through the outlet 10.

During this rinse, the first air supply valve 44 is open, and theflushing means 58 are activated. The first air supply valve 44 is opened1.5 seconds before the liquid supply means 12 are deactivated, and theflushing means are activated 0.5 seconds the liquid supply means 12 aredeactivated. The flushing means remain active for 1.5 seconds. When theflush valve is opened, flush fluid, in this example water, is suppliedto the air duct 42 downstream from the one way valve 60. The flushfluid, in this example water, flows through the air duct 42, into theliquid flow path 14, enters the mixing chamber 8, and exits via theoutlet 10.

When the first air valve 44 is closed, the air pump 54 is activated andthe second air valve 56 is opened. Air is forced through the air duct 42and a portion of the liquid flow path 14. This helps dry out the airduct 42 and the intermediate portion 40 and the first nozzle 34. Thisreduces the amount of mixture residue in the liquid flow path. After 2seconds the air pump 54 is deactivated and the second air valve 56 isclosed. This concludes the beverage cycle. In this example, theresulting beverage consumption has a drink volume of approximately 110ml.

It will be appreciated that the above beverage cycle is an example, andthan many different beverage cycles may be envisioned. It is believedthat the operation and construction of the present invention will beapparent from the foregoing description. For the purpose of clarity anda concise description features are described herein as part of the sameor separate embodiments, however, it will be appreciated that the scopeof the invention may include embodiments having combinations of all orsome of the features described. To the skilled person in this field ofthe art it will be clear that the invention is not limited to theembodiment represented and described here, but that within the frameworkof the appended claims a large number of variants are possible. Alsokinematic inversions are considered inherently disclosed and to bewithin the scope of the present invention. The terms comprising andincluding when used in this description or the appended claims shouldnot be construed in an exclusive or exhaustive sense but rather in aninclusive sense. Expressions such as: “means for . . . ” should be readas: “component configured for . . . ” or “member constructed to . . . ”and should be construed to include equivalents for the structuresdisclosed. The use of expressions like: “critical”, “preferred”,“especially preferred” etc. is not intended to limit the invention.Features which are not specifically or explicitly described or claimedmay be additionally included in the structure according to the presentinvention without deviating from its scope.

1. A beverage preparation unit for preparing beverage consumptions usinga beverage related ingredient; wherein the beverage preparation unitcomprises a mixing chamber having a beverage outlet, a liquid flow pathfor supplying a liquid to the mixing chamber, and an air flow path forsupplying air to the liquid flow path; wherein the mixing chamber isarranged for receiving a beverage related ingredient, such asconcentrate, preferably from an exchangeable supply pack; and whereinthe liquid flow path is arranged for generating a hollow jet of liquidhaving an outer liquid portion extending in a flow direction of the jetand an inner air portion extending in a flow direction of the jetwherein the outer liquid portion surrounds the inner air portion.
 2. Theunit according to claim 1, wherein the liquid flow path includes a firstnozzle.
 3. The unit according to claim 1, wherein the liquid flow pathextends in an axial direction, wherein the unit is further provided withair injection means for generating a flow of air which extends in theaxial direction and for injecting the flow of air substantiallycoaxially in a flow of liquid in the liquid flow path wherein the flowdirection of the flow of liquid in the liquid flow path is the same asthe flow direction of the flow of air so as to obtain the hollow jet. 4.The unit according to claim 3, wherein the injection means comprise aneedle having an open end wherein an axial direction of the needle andan the axial direction of the jet at least substantially coincide. 5.The unit according to claim 4 wherein the open end of the needle islocated near the first nozzle wherein the needle extends from the openend in a direction opposite to the flow direction of the jet.
 6. Theunit according to claim 4 wherein the open end of the needle is locatedin the nozzle, stream upwards of the nozzle or stream downwards of thenozzle.
 7. The unit according to claim 2, wherein the first nozzle isarranged for generating a jet of liquid in an axial direction, andwherein the liquid flow path includes air injection means for injectinga stream of air towards a center of the jet of liquid in a directionsubstantially coaxial with the axial direction of the jet of liquid suchthat a hollow jet is formed.
 8. The unit according to claim 7, whereinthe air injection means include a pipe extending into the first nozzle,wherein the pipe is substantially coaxial with the first nozzle, andwherein the air injection means is arranged for injecting air into thejet of liquid generated by the first nozzle through the pipe.
 9. Theunit according to claim 3, wherein the air injection means is arrangedto be in fluid communication with an air pump.
 10. The unit according toclaim 4, wherein the liquid flow path includes a selection valvecomprising a valve body, a liquid inlet arranged to be in fluidcommunication with a liquid supply means, an air inlet arranged to be influid communication with an air injection means, and at least a firstoutlet in fluid communication with the mixing chamber, wherein theselection valve further comprises a selector member including theneedle, wherein the selector member is movably mounted with respect tothe valve body for movement from a first position in which the liquidinlet is in fluid communication with the at least first outlet, andwherein the air inlet is in fluid communication with the at least firstoutlet via the needle of the selector member. 11-14. (canceled)
 15. Theunit according to claim 10, wherein the valve further includes asatellite element including the first nozzle, wherein the satellitemember is associated with the selector member, and wherein the satelliteelement has a predefined limited amount of free relative movement withrespect to the selector member for allowing the satellite element to beposition independently of the selector member, and wherein in the firstposition the liquid inlet and air inlet are in fluid communicationthrough a fluid flow path including the first nozzle of the satellitemember. 16-18. (canceled)
 19. The unit according to claim 2, wherein thefirst nozzle terminates at a side wall of the mixing chamber, andwherein the outer liquid portion of the hollow jet contacts asubstantial portion of an inner surface of the first nozzle in an areaadjacent to the mixing chamber. 20-25. (canceled)
 26. The unit accordingto claim 2, wherein the air flow path comprises an air supply duct influid communication with the liquid flow path and located upstream fromthe first nozzle, and preferably the air supply duct is connected to theintermediate portion of the liquid flow path.
 27. The unit according toclaim 26, wherein the air flow path comprises a first air supply valvearranged for selectively connecting the air supply duct to an airsupply, preferably to atmosphere. 28-29. (canceled)
 30. The unitaccording to claim 26, wherein the air flow path further comprises anair pump arranged for actively supplying air to the liquid flow path viathe air supply duct.
 31. The unit according to claim 30, wherein the airflow path further comprises a second air supply valve arranged forselectively connecting the air pump to the air supply duct. 32-33.(canceled)
 34. The unit according to claim 31, wherein the beveragepreparation device is arranged for activating the air pump and openingthe second air valve when activating the drive shaft.
 35. The unitaccording to claim 26, wherein the air supply duct includes a one wayvalve arranged to prevent liquid from traveling along the air supplyduct.
 36. (canceled)
 37. A beverage preparation device for preparingbeverage consumptions, the device comprising: a beverage preparationunit, wherein the beverage preparation unit comprises a mixing chamberhaving a beverage outlet, a liquid flow path for supplying a liquid tothe mixing chamber, and an air flow path for supplying air to the liquidflow path; wherein the mixing chamber is arranged for receiving abeverage related ingredient, such as concentrate, preferably from anexchangeable supply pack; and wherein the liquid flow path is arrangedfor generating a hollow jet of liquid having an outer liquid portionextending in a flow direction of the jet and an inner air portionextending in a flow direction of the jet wherein the outer liquidportion surrounds the inner air portion; liquid supply means includingthe liquid flow path for supplying a liquid to the mixing chamber; andair supply means for supplying air to the liquid flow path. 38.(canceled)
 39. The beverage preparation device according to claim 37,wherein the beverage preparation device further comprises anexchangeable supply pack compartment for receiving an exchangeablesupply pack with beverage related ingredients, and wherein preferablythe compartment is closed by a openable hatch. 40-41. (canceled)
 42. Asystem for preparing beverage consumptions, the system comprising: abeverage preparation device according to claim 37; at least oneexchangeable supply pack arranged for holding a beverage relatedingredient; wherein the beverage preparation device further comprises adoser interface; wherein the at least one exchangeable supply packincludes a container for holding a beverage related ingredient, and adoser having an outlet, wherein the doser is arranged for supplying thebeverage related ingredient from the container to the outlet of thedoser in a dosed manner; wherein the at least one exchangeable supplypack and the beverage preparation device are mechanically connectable,and wherein when connected the outlet of the doser is brought in fluidcommunication with the mixing chamber and the doser interface isarranged for activating the doser for supplying beverage relatedingredient from the outlet of the doser into the mixing chamber.
 43. Acombination of a beverage preparation unit according to claim 1 and anair pump, wherein air flow path of the unit is arranged to be in fluidcommunication with the air pump, and wherein preferably the air pump isarranged for supplying air to the air flow path at a pressure in therange of 0.05 bar-10 bar, preferably 0.1 bar-0.3 bar, and mostpreferably 0.1 bar-0.2 bar.
 44. A combination of a beverage preparationunit according to claim 1 and a liquid pump, such as a water pump,wherein the liquid flow path of the unit is arranged to be in fluidcommunication with the liquid pump and wherein preferably the liquidpump is arranged for supplying liquid to the liquid flow path at apressure in the range of 0.5 bar-15 bar, preferably 1 bar-7 bar, andmost preferably 1.5 bar-3 bar.